Controls for transducer drive on a telephone dialer



J. W. HEALY Aug. 25, 1964 CONTROLS FOR TRANSDUCER DRIVE ON A TELEPHONE DIALER 2 Sheets-Sheet 1 Filed Dec. 31, 1962 INVENTOR. JAMES W. HEAL Y BY J r Aug. 25, 1964 J. w. HEALY 3,145,313

CONTROLS F OR TRANSDUCER DRIVE ON A TELEPHONE DIALER Filed Dec. 31, 1962 2 Sheets-Sheet 2 INVENTOR. JAMES W- HEALY United States Patent CONTROLS FOR TRANSDUCER DRIVE ON A TELEPHONE DIALER James W. Healy, Wakefield, Mass., assignor to Perini Electronic Corporation, San Mateo, Calif., a corporation of California Filed Dec. 31, 1962, Ser. No. 248,604 7 Claims. (Cl. 192--.02)

This invention relates to automatic telephone dialers and particularly to the controls for initiating a dialing cycle in a dialer of the magnetic storage type.

The dialer with which the controls of the present invention are used comprises a magnetizable medium in the form of a tape upon which telephone numbers are encoded. Reading the coded numbers and transforming them into impulses on a telephone circuit is accomplished by means including a transducer mounted to be driven across or scan the tape under the power of an electric motor.

It is an object of the present invention to provide improved manually actuated means to effect return of the transducer to its home or starting position and to close a circuit to the motor to initiate a new dialing cycle.

A further object of the invention is to provide means operable upon starting a cycle to disengage a clutch between the motor and transducer drive, to latch the clutch in disengaged position, and to effect release of the latch and reengagement of the clutch only upon arrival of the transducer at its home position.

Another object of the invention is to provide a second means for energizing the motor without disengaging the clutch so that the transducer may be driven from an intermediate position where it has been interrupted for reasons hereinafter set forth in detail.

Still further and more specific objects and advantages of the invention are made apparent in the following specification by reference to the accompanying drawings wherein the invention is disclosed in detail.

In the drawings:

FIG. 1 is a view in side elevation of a portion of the frame of an automatic telephone dialer showing the components of the present invention in place thereon;

FIG. 2 is a plan view of the forward portion of the frame shown in FIG. 1 and particularly illustrating a latch mechanism;

FIG. 3 is a sectional view with parts removed taken on the line IIIIII of FIG. 1; and

FIG. 4 is a plan view with parts removed taken on the line IV-IV of FIG. 3.

In FIG. 1 of the drawings, a base plate of an automatic telephone dialer is disclosed as supporting a motor 11 and reduction gear box 12 for driving a shaft 13. Fixed to the shaft is the driving part of a serrated face type clutch 14, the driven part of which 15 is on a hub 16 which also supports a chain sprocket 17 and a spring spool 18 upon which a spring 19 is wound. The chain is shown at 20 and as best illustrated in FIG. 3 is an endless chain trained over an idler sprocket 21.

A transducer head shown at 22 is mounted on a carriage 23 which is supported for sliding movement with respect to bars 24 and 25. When the motor 11 is in operation and the clutch 1415 engaged as shown in FIG. 1, the transducer, being fixed to the chain 20, is caused to move from left to right as viewed in FIG. 3 to scan a tape (not shown) in FIG. 3 but a portion of which is illustrated at 27 in FIG. 4. The spring 19 is anchored as at 28 in FIG. 3 and since the spool 18 upon which it is wound is fixed on the same hub as the sprocket 17 advancing of the transducer to the right, as viewed in FIG. 3, turns the spool 14 in a counterclockwise direction tensioning the spring so that upon release of the transducer by disengagement of the clutch 14-15 the spring will effect return of the transducer to the home position in which it is shown. In the operation of the automatic telephone dialer in which the present controls are employed, energization of the motor 11 effects movement of the transducer from the home position in a rightward direction so that it scans the tape 27 and reads or decodes a message in the form of a telephone number which has been encoded upon the tape as spaced magnetic bits. The machine also contains means, a disclosure of which is not necessary to an understanding of the present invention, to deenergize the motor 11 permitting the transducer to come to rest when it has scanned the entire telephone number on the tape and traveled a distance sufficient to indicate that the number has been completely decoded. Thus the transducer stops in a position to the right of that shown in FIG. 3, which will be termed a rest position, where it remains until the initiation of another decoding cycle being held against return by engagement of the clutch 14-15. Consequently when a second dialing or decoding cycle is initiated, the transducer must be returned from its rest position to its home position from which it may again scan the tape in a rightward direction.

Initiation of a dealing cycle is effected by depression of a key shown at 30 in FIG. 1 which is mounted on a lever 31 pivotally supported to a frame plate 32 at 33. The lever 31 is also pivotally connected to a slidable bar 34, one end of which has an upstanding clutch actuating finger 35 extending into the space between the driven part 15 of the clutch and the spool 18. Consequently depression of the starter key 30 slides the bar 34 toward the left and releases the clutch by sliding the driven part 15 to the disengaged position shown in FIG. 4, it being understood that this part as well as the hub 16, spool 18 and sprocket 17 are all slidably mounted on the shaft 13. To energize the motor a micro-switch in circuit therewith is shown at 37 in FIG. 1 as having a depressible button 38. Momentary depression of the button 38 effects energization of the motor through a suitable relay circuit not shown. The button 38 is depressed by counterclockwise rotation of a ratchet wheel 39 and a pawl 40 pivoted to the control bar is advanced one tooth on the ratchet upon depression of the key 30 and movement of the bar 34 to the left so that upon return of the bar 34 under influence of a spring 43, the pawl will advance the ratchet wheel 39 one tooth in a counterclockwise direction effecting momentary depression of the button 38. A spring 44 urges the pawl upwardly into contact with the ratchet wheel.

It is desirable to prevent reengagement of the clutch 14-15 until the transducer has moved from its rest position to its home position in which it is illustrated in FIG. 3. To accomplish this, the control bar 34 is latched in its advanced position with the clutch disengaged by latch mechanism best shown in FIGS. 1 and 2. This latch mechanism comprises a lever 46 pivoted at 47 to a lug 48 on the frame 32. The latch is urged to swing in a clockwise direction by a spring 49 and has a pawl 58 which drops behind a pin 51 carried by a lug 52 on the control bar 34. Thus when the control bar is advanced by depression of the key 30, it is latched in its advanced position with the clutch in a disengaged position and the pawl 40 poised to actuate the ratchet wheel 39 and energize the motor when the control bar returns. The

latch lever 46 also has an end 54 disposed in a position to be engaged by the transducer carriage 23 when the transducer reaches its home position and this engagement swings the lever 46 in a counterclockwise direction releasing the latching connection of the pin 51 and the pawl 50 so that the control bar can be returned under influence of its spring 43.

Thus when the key 30 is depressed, the clutch is disengaged and held disengaged by the control bar latch for the brief instant required for the spring 19 to return the transducer head to its home position whereupon the latch is released and the control bar returns restoring the clutch to its engaged position and energizing the switch to the motor. Through this mechanism, it is impossible for the motor to drive the transducer until there is positive assurance that the transducer has reached its home position.

In the operation of an automatic telephone dialer which meets the needs of present day telephony, it is sometimes necessary for the transducer to pause during a decoding cycle and then continue its scanning operation to read a further part of the number. This is necessitated by the fact that some numbers are formed in two parts, the first part being employed as in nine level dialing or in direct distance dialing to form a connection with another telephone circuit into which a number must be dialed. When a connection with such a telephone circuit is established, indication is given by a dial tone advising the calling party that dialing can be resumed. In dialing of such numbers, the coding arrangement thereof on the tape of the present automatic telephone dialer will be so spaced that the transducer head will come to rest after completion of the first number and will remain at rest until a dial tone is received and the calling party again starts the transducer in motion. This second part of the dialing cycle cannot be initiated by the key 30 because depression thereof causes return of the dial to its home position. For this reason, a second or auxiliary key 54 is provided and is carried on a lever 55 pivotally connected to the frame 32 by means of a pin 56. The lever 55 has a downwardly extending finger 57 engaging the end of the pawl 4-0. Thus depression of the key 54 advances the pawl 40 one tooth on the ratchet wheel 39 which is made possible by a slot 53 in the pawl embracing its pivot pin 41. When the key 54 is released, the pawl spring 44 efiects return of the pawl and rotation of the ratchet wheel to close the switch 7 and energize the motor 11. Thus the motor has been reenergized without disengaging the clutch which would result in return of the transducer head to its home position. A small spring shown at 60 serves to retain the lever 55 against downward movement when the control bar 34 and pawl 40 are advanced by means of the key 30. The control bar 34 also has a fiat upstanding portion 61 lying between the key lever 55 and the frame plate 32 to stabilize the control bar and this portion 61 is provided with a slot 62 which embraces the pivot pin 56 and permits forward movement of the control bar with respect thereto.

I claim:

1. In controls for a transducer drive on a telephone dialer or the like which include a motor for driving the transducer, a clutch between the motor and transducer, a switch for energizing the motor and spring means to return the transducer from a rest position to a home position, key actuated means to disengage the clutch to permit return of the transducer by the spring means, a latch to retain the clutch in disengaged position, and means actuated by movement of the transducer to home position to disengage said latch.

2. The combintion of claim 1 in which resilient means effect engagement of the clutch upon release of said latch.

3. The combination of claim 2 with means to close the switch to the motor as the clutch is engaged.

4. The combination of claim 1 with a second key actuated means to elfect energization of the motor without disengaging the clutch.

5. In controls for a transducer drive in a telephone dialer or the like including a motor, a clutch and a spring to return the transducer from a rest to a home position when the clutch is disengaged, a key, a slidable control bar advanceable by depression of the key, means to disengage the clutch upon advance of the bar, a spring to return the bar and engage the clutch, a latch to retain the bar in its advanced position, and means actuated by return of the transducer to home position to release said latch and permit engagement of the clutch only after return of the transducer.

6. The combination of claim 5 with a switch to energize the motor, a ratchet wheel with teeth arranged to close the switch, a pawl on said control bar engaging the ratchet wheel and advanced one tooth thereon upon advance of the control bar whereby the ratchet wheel will be turned and the switch closed upon return of the control bar.

7. The combination of claim 6 with a second key engageable with the pawl to advance the pawl and effect closing of the switch without advancing the control bar.

OTHER REFERENCES lggiasz German printed application 1,116,740, Nov. 9, 

1. IN CONTROLS FOR A TRANSDUCER DRIVE ON A TELEPHONE DIALER OR THE LIKE WHICH INCLUDE A MOTOR FOR DRIVING THE TRANSDUCER, A CLUTCH BETWEEN THE MOTOR AND TRANSDUCER, A SWITCH FOR ENERGIZING THE MOTOR AND SPRING MEANS TO RETURN THE TRANSDUCER FROM A REST POSITION TO A HOME POSITION, KEY ACTUATED MEANS TO DISENGAGE THE CLUTCH TO PERMIT RETURN OF THE TRANSDUCER BY THE SPRING MEANS, A LATCH TO RETAIN THE CLUTCH IN DISENGAGED POSITION, AND MEANS ACTUATED BY MOVEMENT OF THE TRANSDUCER TO HOME POSITION TO DISENGAGE SAID LATCH. 